Kaleidoscope March 2017

March’s Kaleidoscope column in the British Journal of
Psychiatry explores novel psychoactive substances (NPS or
(inaccurately) ‘legal highs’), particularly novel
cannabinoids. The law in the UK changed in 2016,
proscribing all psychoactive agents, including those not yet
synthesised, except for those specifically exempted (e.g.
antidepressants, alcohol etc.). How effective this will be has yet
to be seen: so-called ‘headshops’ are shutting down, returning
local drug purchasing to the realm of meeting a guy on a BMX bike
with a knife in his pocket – a pyrrhic victory perhaps.
Problematically, with over 500 novel agents, science and clinical
practice are only coming to terms with NPS, and some of the novel
cannabinoids are being identified as ‘ultra-potent’. Kaleidoscope
picks up on a paper from the New England Journal of Medicine that
describes a ‘zombie outbreak’ due to the highly depressant effects
of a specific new agent identified. Long term concerns about
potential impact on younger users continue. Changing tack, a
fascinating editorial in the main journal by Matthew Nour and Robin
Carhart-Harris re-evaluates psychedelics: this particular class of
drug has never been as harmful as its reputation or notoriety might
predict, and indeed it may have much to tell us about the science
of ‘self’.

Which factors predict the development of PTSD following
exposure to a trauma? There are growing data that
interpersonal traumas, such as a sexual assault, are more damaging
than non-interpersonal ones, such as road traffic accidents. The
issue of individual predisposition has also attracted much
attention: why, when faced with a similar trauma, do some but not
others develop this condition? Problematically, much of the
existing literature has had quite small sample sizes, challenging
the validity and reproducibility of the findings. Now a large study
has utilised data from almost 35,000 participants in a World Health
Organisation survey. One’s past history also matters, and fitting
with precipitating trauma data, a past history of violent traumas –
but not other types – sensitises one to having later life PTSD
triggered by subsequent events. Fascinatingly, the work also found
an unexpectedly low prevalence of PTSD after natural disasters, and
the authors argue that some past smaller studies suffered
unintentional biases by focusing primarily on highly traumatised
subpopulations.

How do you define pseudohallucinations? Am I alone in
repeatedly stumbling with my response to that perennial question
from medical students? I suspect that the ‘pseudo’ =
‘false’, and the presumed marriage to borderline personality
disorder just jar with me. In any case, most clinicians will
recognise the phenomenon, and likely associate it closely with BPD.
Ian Kelleher and Jordan DeVylder challenge us in this month’s
BJPsych, showing that epidemiological data show
hallucinations/voice hearing to be equally common across the whole
range of non-psychoses. They propose that the nature of BPD makes
it more likely that individuals disclose/seek help for voices. It’s
always good to have our assumptions tested.

Finally, do check out (and join in the debate by
commenting on) Joe Hayes’ great blog, part of a new initiative
between the BJPsych and the Mental Elf, on Tsoi et al’s paper in
this month’s journal on depression severity and CBT
outcomes:http://bit.ly/cbt-severe

March's Kaleidoscope Monthly Quiz (True/False)

Q1: The Novel Psychoactive Substance
legislative Act of 2016 has banned possession of all current and
future so-called ‘legal highs’.A1: False. Sale and distribution are banned,
possession is not.

Q2: Past participation in sectarian violence
has been shown to be associated with enhanced resilience to the
later development of PTSD.A2: True, but it is considered likely to be a
selection bias: those who choose to engage in such violence are
temperamentally different.

Q3: A large neuroimaging study has shown that
‘depression’ can be clustered into four neuroimaged biotypes, and
these will predict response to neuromodulation treatment.A3: True.